Tornado-ravaged city of Moore, Okla., to hold Sunday memorial

Lightning strikes during a thunderstorm as tornado survivors search for salvagable items at their devastated home on May 23, in Moore, Okla.

By Gabe Guttierez and Tracy Connor, NBC News

The decimated city of Moore, Okla., will hold a public memorial service Sunday evening, six days after a tornado killed 24 people, injured 377 and destroyed hundreds of homes.

Gov. Mary Fallin said the prayer service at the First Baptist Church will be "open to all," though it was unclear if President Barack Obama, who is visiting Oklahoma that day, will attend.

The gathering will be the first opportunity for the suburb of 56,000 to mourn and take stock as a community since the twister came through with apocalyptic force on Monday afternoon, wrecking houses, businesses, schools and lives.

The landscape of the community will be scarred for some time, but the mood in Moore seemed to be shifting from awe and disbelief to resolve to carry on.

"We will rebuild and we will reopen and we will have school in August," vowed city school superintendent Susan Pierce, even as she wept while talking about the first funeral of a student held Thursday.

Oklahoma Gov. Mary Fallin announces that a memorial and prayer service will be held this Sunday for tornado victims adding, "we can honor those we have lost, pray for those they left behind, and begin to heal together."

"I've never been more proud to be a member of a community," said Pierce, who has lived in Moore since 1960.

Officials praised citizens of the town for pulling together to help those who had lost everything.

More than 20 Red Cross vehicles were handing out meals and offering mental health counseling Thursday. Diana Mitchell, a retired nurse from Enid, Okla., who has been working in health care for 42 years, was manning one of the trucks.

"My husband decided we needed something to do," she said with a smile.

And cemeteries that had asked for assistance removing debris in time for the Memorial Day weekend were stunned when 1,500 people showed up to help.

On a street near the a hospital that had been destroyed, volunteers were cleaning up the home of a neighbor they barely know.

“These citizens are awesome. I mean they’ve lost everything but they’ve still got a sense of humor,” said Moore deputy city manager Stan Drake.

Officials were also focusing on the strides made in the chaotic post-storm days: Since Monday's twister hit, 2,200 people have registered for help with the Federal Emergency Management Agency, the state legislature has released $45 million in aid, and six people who were thought to be missing have been found.

One of them had put a note on their door that said, "Tornado's coming. I've left."